Comparative pharmacokinetics and safety assessment of transdermal berberine and dihydroberberine

The natural alkaloid berberine has been ascribed numerous health benefits including lipid and cholesterol reduction and improved insulin sensitivity in diabetics. However, oral (PO) administration of berberine is hindered by poor bioavailability and increasing dose often elicits gastro-intestinal side effects. To overcome the caveats associated with oral berberine, we developed transdermal (TD) formulations of berberine (BBR) and the berberine precursor dihydroberberine (DHB). These formulations were compared to oral BBR using pharmacokinetics, metabolism, and general safety studies in vivo. To complete this work, a sensitive quantitative LC-MS/MS method was developed and validated according the FDA guidelines for bioanalytical methods to simultaneously measure berberine, simvastatin, and simvastatin hydroxy acid with relative quantification used for the berberine metabolite demethylene berberine glucuronide (DBG). Acute pharmacokinetics in Sprague-Dawley rats demonstrated a statistically relevant ranking for berberine bioavailability based upon AUC_0-8 as DHB TD > BBR TD >> BBR PO with similar ranking for the metabolite DBG, indicating that transdermal administration achieves BBR levels well above oral administration. Similarly, chronic administration (14 days) resulted in significantly higher levels of circulating BBR and DBG in DHB TD treated animals. Chronically treated rats were given a single dose of simvastatin with no observed change in the drugs bioavailability compared with control, suggesting the increased presence of BBR had no effect on simvastatin metabolism. This observation was further supported by consistent CYP3A4 expression across all treatment groups. Moreover, no changes in kidney and liver biomarkers, including alanine aminotransferase and alkaline phosphatase, were observed between treatment formats, and confirming previous reports that BBR has no effect on HMG-CoA expression. This study supports the safe use of transdermal compositions that improve on the poor bioavailability of oral berberine and have the potential to be more efficacious in the treatment of dyslipidemia or hypercholesterolemia.

[Quantitative analysis of four alkaloids in Xianglian preparations by QAMS method]

OBJECTIVE

To examine the feasibilities of the method, quantitative analysis of multi-components by single marker (QAMS) for determination of four alkaloids in Xianglian preparations.

METHOD

A HPLC method was developed to determine the contents of four alkaloids, epiberberine, coptisine, palmatine and berberine in Xianglian preparations. Berberine was selected as the internal reference substance, and 3 relative correction factors to berberine were calculated. The contents of the four alkaloids in 16 batches of samples were determined by both external standard method and QAMS. The new method was evaluated by comparing the quantitative results with of the external standard method.

RESULT

No significant differences were found between the quantitative results of four alkaloids in 16 batches of samples determined by the two methods.

CONCLUSION

QAMS is feasible for determination of four alkaloids simultaneously, and the developed method can be used for quality control of Xiang Lian preparations.

[Quality analysis and evaluation of Rhizoma Coptidis under different cultivation conditions]

AIM

To develop methods for the fingerprint analysis of Rhizoma Coptidis and the determination of berberine, palmatine and jatrorrhizine in Rhizoma Coptidis, and analyze the contents of these three alkaloids in Rhizoma Coptidis under different cultivation conditions, from different areas and processed with different methods.

METHODS

Two methods (HPLC-UV and HPLC-MS) have been developed and used in fingerprint analysis of Rhizoma Coptidis. An HPLC method was used to determine the contents of three alkaloids.

RESULTS

With HPLC-MS techniques, seven major chromatographic peaks in the fingerprint analysis of Rhizoma Coptidis were identified by their MS spectra and compared with the reference standards. In different cultivation conditions, shading conditions and growing ages have obvious influence on the contents of three alkaloids in Rhizoma Coptidis, while planting density was not the major factor that influenced the contents of three alkaloids. The contents of three alkaloids of Coptidis samples were almost higher than those of Coptidis reference material. For Coptidis samples from different cultivation area, the contents of these three alkaloids were different greatly. For Coptidis samples processed with different methods, the contents of three alkaloids were not influenced obviously by processing methods.

CONCLUSION

The results showed that the ecology cultivation method to replace the traditional shading method was feasible and provided the theoretical foundation for scientifically processing Rhizoma Coptidis.

[Berberine Hydrochloride Reference Standard (Control 001) of National Institute of Health Sciences]

The raw material of Berberine Hydrochloride was examined for preparation of the "Berberine Hydrochloride Reference Standard". The analytical data obtained were: UV spectrum: lambda max, 420, 345, 263 and 228 nm and specific absorbance (E1ca1%) in ethanol at each lambda max, 155, 724, 796 and 820, respectively; IR spectrum, specific absorptions at 2844, 1635, 1569, and 1506 cm-1; and the spectrum of raw material was consistent with that of Standard (Control 941). Also, thin-layer chromatography, an impurity was detected; high-performance liquid chromatography, several impurities were detected. The amount of each impurity was estimated at less than 0.1% and the total amount of impurities was less than 0.2%. Based on the above results, the candidate material was authorized as the Berberine Hydrochloride Reference Standard (Control 001) of the National Institute of Health Sciences.